Balance-Compensated Asymmetric Marchand Baluns on Silicon for MMICs

The balance compensating techniques for asymmetric Marchand balun are presented in this letter. The amplitude and phase difference are characterized explicitly by S
₂₁
and S
₃₁
, from which the factors responsible for the balance compensating are determined. Finally, two asymmetric Marchand baluns, which have normal and enhanced balance compensation, respectively, are designed and fabricated in a 0.18 μm CMOS technology for demonstration. The simulation and measurement results show that the proposed balance compensating techniques are valid in a very wide frequency range up to millimeter-wave (MMW) band.